Using Datadirect Connect for ADO.NET with Oracle RAC
Oracle RAC, as implemented in Oracle 9i and Oracle 10g, allows a single physical Oracle database to be accessed by concurrent instances of Oracle running across different CPUs. This document explains how the Progress DataDirect Connect for ADO.NET Oracle data provider can connect to an Oracle RAC system as if it was a single instance of an Oracle database. The data provider can use a connection string or retrieve specific connection information from a tnsnames.ora file.
This document also describes the two failover methods that Oracle RAC uses to provide reliable access to data replicated on multiple servers: connection failover and transparent application failover (TAF). In addition, this document explains how you can take advantage of these failover methods when you use the DataDirect Connect for ADO.NET Oracle data provider to connect your data critical applications to data.
Oracle RAC systems provide two types of load balancing for automatic workload management: server load balancing, which distributes processing, and client load balancing, which distributes connection attempts. The DataDirect Connect for ADO.NET Oracle data provider supports both types of load balancing. Client load balancing can be enabled through a connection string option or in the tnsnames.ora file.
NOTE: Code examples in this document use the ADO.NET 2.0 Common Programming Model and MetaData capabilities introduced in the Microsoft .NET 2.0 Framework. If you are using an earlier version of the .NET Framework or the DataDirect Connect for .NET 2.2 data providers, refer to "Using DataDirect Connect® for .NET with Oracle Real Application Clusters (RAC)".
